fix: response_formatter doesnt work well in vllm + phi4

Author: vizsatiz

flo_ai/flo_ai/llm/openai_vllm.py

@@ -37,14 +37,13 @@ async def generate(
             if messages and messages[0]['role'] == 'system':
                 messages[0]['content'] = (
                     messages[0]['content']
-                    + '\n\nPlease provide your response in JSON format according to the specified schema.'
+                    + f'\n\nPlease provide your response in JSON format according to the specified schema. \n\n {output_schema}'
                 )
             else:
                 messages.insert(
-                    0,
                     {
                         'role': 'system',
-                        'content': 'Please provide your response in JSON format according to the specified schema.',
+                        'content': f'Please provide your response in JSON format according to the specified schema.\n \n {output_schema}',
                     },
                 )